Same frame motion estimation and compensation

ABSTRACT

Motion estimation or compensation functionality of a hardware component is used to encode or decode key frames and other video frames. The hardware component includes a memory, which may, for example, be a local static random access memory or an external dynamic random access memory. Upon a block of a frame being encoded or decoded, data associated with that block is stored in the memory. That data can then be processed by motion estimation or motion compensation for use in encoding or decoding one or more later blocks within the same frame. The data may, for example, be stored in the memory after operations for reconstruction and loop filtering have been performed. The data stored in the memory may effectively be processed using traditional inter-prediction operations, such as to identify similar video objects within blocks of the same frame.

CROSS REFERENCE TO RELATED APPLICATION(S)

This disclosure claims the benefit of U.S. Provisional Application No.62/576,274, filed Oct. 24, 2017, the disclosure of which is herebyincorporated by reference in its entirety.

BACKGROUND

Digital video streams may represent video using a sequence of frames orstill images. Digital video can be used for various applicationsincluding, for example, video conferencing, high definition videoentertainment, video advertisements, or sharing of user-generatedvideos. A digital video stream can contain a large amount of data andconsume a significant amount of computing or communication resources ofa computing device for processing, transmission, or storage of the videodata. Various approaches have been proposed to reduce the amount of datain video streams, including encoding or decoding techniques.

SUMMARY

A method for encoding a current block of a video frame according to animplementation of this disclosure comprises identifying a first set ofmotion vector candidates by performing motion estimation based on firstdata stored in a memory. The first data is associated with one or moreencoded blocks preceding the current block within the video frame and isstored in the memory subsequent to an encoding of the one or moreencoded blocks. The method further comprises identifying a second set ofmotion vector candidates by performing inter-prediction against at leastone encoded block of at least one previously encoded video frame. Themethod further comprises selecting at least one motion vector from atleast one of the first set of motion vector candidates or the second setof motion vector candidates. The method further comprises determining aprediction residual block for the current block using a prediction blockgenerated based on the selected at least one motion vector. The methodfurther comprises transforming the prediction residual block to producetransform coefficients. The method further comprises quantizing thetransform coefficients to produce quantization coefficients. The methodfurther comprises reconstructing the quantization coefficients toproduce a reconstructed current block. The method further comprisesstoring second data in the memory for use in encoding a video blockfollowing the current block within the video frame. The second data isindicative of a video object associated with the reconstructed currentblock.

An apparatus for encoding a current block of a video frame according toan implementation of this disclosure comprises a processor configured toexecute instructions stored in a non-transitory storage medium. Theinstructions include instructions to identify a first set of motionvector candidates by performing motion estimation based on first datastored in a memory. The first data is associated with one or moreencoded blocks preceding the current block within the video frame and isstored in the memory subsequent to an encoding of the one or moreencoded blocks. The instructions further include instructions toidentify a second set of motion vector candidates by performinginter-prediction against at least one encoded block of at least onepreviously encoded video frame. The instructions further includeinstructions to select at least one motion vector from at least one ofthe first set of motion vector candidates or the second set of motionvector candidates. The instructions further include instructions todetermine a prediction residual block for the current block using aprediction block generated based on the selected at least one motionvector. The instructions further include instructions to transform theprediction residual block to produce transform coefficients. Theinstructions further include instructions to quantize the transformcoefficients to produce quantization coefficients. The instructionsfurther include instructions to reconstruct the quantizationcoefficients to produce a reconstructed current block. The instructionsfurther include instructions to store second data in the memory for usein encoding a video block following the current block within the videoframe. The second data is indicative of a video object associated withthe reconstructed current block.

A method for decoding an encoded block of an encoded video frame from abitstream according to an implementation of this disclosure comprisesdecoding one or more syntax elements from the bitstream. The one or moresyntax elements indicate to decode the encoded block by performingmotion compensation against one or more reconstructed blocks of theencoded video frame. The method further comprises decoding at least onemotion vector from the bitstream and performing motion compensationbased on first data stored in a memory. The first data is associatedwith the one or more reconstructed blocks. The first data is stored inthe memory subsequent to a reconstruction of the one or morereconstructed blocks. The method further comprises generating aprediction block using the decoded at least one motion vector. Themethod further comprises dequantizing coefficients of the encoded blockto produce dequantization coefficients. The method further comprisesinverse transforming the dequantization coefficients to reconstruct aprediction residual block. The method further comprises combining theprediction residual block and the prediction block to produce areconstructed block. The method further comprises storing second data inthe memory for use in decoding a video block following the encoded blockwithin the encoded video frame. The second data is indicative of a videoobject associated with the reconstructed block.

These and other aspects of the present disclosure are disclosed in thefollowing detailed description of the embodiments, the appended claimsand the accompanying figures.

BRIEF DESCRIPTION OF THE DRAWINGS

The description herein makes reference to the accompanying drawingsdescribed below, wherein like reference numerals refer to like partsthroughout the several views.

FIG. 1 is a schematic of a video encoding and decoding system.

FIG. 2 is a block diagram of an example of a computing device that canimplement a transmitting station or a receiving station.

FIG. 3 is a diagram of a typical video stream to be encoded andsubsequently decoded.

FIG. 4 is a block diagram of an encoder according to implementations ofthis disclosure.

FIG. 5 is a block diagram of a decoder according to implementations ofthis disclosure.

FIG. 6 is a flowchart diagram of an example of a technique for encodinga current block of a video frame using same frame motion estimation.

FIG. 7 is a flowchart diagram of an example of a technique for decodingan encoded block of an encoded video frame using same frame motioncompensation.

FIG. 8 is an illustration of a video frame including a current blockcoded using same frame motion estimation and compensation.

FIG. 9 is an illustration of tiles of a video frame including currentblocks parallel coded using same frame motion estimation andcompensation.

FIG. 10 is a block diagram of a hardware component configured forencoding a current block of a video frame using same frame motionestimation.

FIG. 11 is a block diagram of a hardware component configured fordecoding an encoded block of an encoded video frame using same framemotion compensation.

DETAILED DESCRIPTION

Video compression schemes may include breaking respective images, orframes, into smaller portions, such as blocks, and generating an outputbitstream using techniques to limit the information included forrespective blocks in the output. An encoded bitstream can be decoded tore-create the source images from the limited information. Typical videocompression and decompression techniques use regular motioncompensation, which use inter-frame redundancies to predict motion basedon temporal similarities between video frames or intra-frameredundancies to predict motion based on spatial similarities withinindividual video frames.

In some cases, a hardware component may be configured to encode an inputvideo stream including frames into a compressed bitstream and/or todecode a compressed bitstream into an output video stream for display.The hardware component may, for example, include functionality forpredicting motion during encoding and/or decoding, such as by leveragingmotion estimation or compensation to identify inter-frame redundancies.Motion estimation and compensation, and thus inter-predictionoperations, are typically used only to predict motion against data ofother frames. However, a video sequence may include frames that cannotbe predicted using other frames.

For example, the video sequence may include one or more key frames thatmay include video objects distinct from other frames. A key frame may,for example, be the first frame in a video sequence, a first frameassociated with a new scene displayed in a video sequence, a frame towhich a viewer of a video sequence has skipped or jumped to, or thelike. The entire image of a key frame is typically encoded to acompressed bitstream since it may not be otherwise identifiable, suchthat portions of the key frame may be lost if not encoded. A key framemay thus require more bandwidth and power to encode or decode than othertypes of frames. In cases where a hardware component is used, the motionestimation or compensation functionality may be idle during theprocessing of a key frame. This is because the key frame is not encodedor decoded using inter-frame redundancies.

Implementations of this disclosure include using motion estimation orcompensation functionality of a hardware component to encode or decodekey frames and other video frames. The hardware component includes amemory (e.g., a local static random access memory (SRAM), a dynamicrandom access memory (DRAM), or the like). Upon a block of a frame beingencoded or decoded, data associated with that block is stored in thememory. That data can then be processed by motion estimation (e.g.,during encoding) or motion compensation (e.g., during decoding) for usein encoding or decoding one or more later blocks within the same frame.The data may, for example, be stored in the memory after operations forreconstruction and loop filtering have been performed against the blockduring the encoding or decoding. The data stored in the memory mayeffectively be processed using traditional inter-prediction operations,such as to identify similar video objects within blocks of the sameframe.

By storing the data in a local static memory and using that stored datato predict data for later blocks of the same frame, for example, thehardware component does not have to access an external memory. Theimplementations of this disclosure may therefore reduce the amount ofbandwidth and power otherwise required to encode or decode video datausing a hardware component. However, in some implementations where thedata used to encode or decode a block is stored in an external memory(e.g., an external DRAM), those implementations may still reduce anamount of bandwidth and power otherwise required for encoding ordecoding, such as where the data stored in such external DRAM or likememory is used to encode or decode a key frame. Although such a resultmay be easily recognizable when processing key frames, theimplementations of this disclosure provide benefits for processing othertypes of frames, as well. For example, the resources required forprocessing non-key frames that include abrupt changes in content,lighting, fast motion, or the like may also be reduced using theimplementations of this disclosure.

Further details of techniques for using motion estimation orcompensation functionality of a hardware component to encode or decodekey frames and other video frames are described herein with initialreference to a system in which they can be implemented. FIG. 1 is aschematic of a video encoding and decoding system 100. A transmittingstation 102 can be, for example, a computer having an internalconfiguration of hardware such as that described in FIG. 2. However,other implementations of the transmitting station 102 are possible. Forexample, the processing of the transmitting station 102 can bedistributed among multiple devices.

A network 104 can connect the transmitting station 102 and a receivingstation 106 for encoding and decoding of the video stream. Specifically,the video stream can be encoded in the transmitting station 102, and theencoded video stream can be decoded in the receiving station 106. Thenetwork 104 can be, for example, the Internet. The network 104 can alsobe a local area network (LAN), wide area network (WAN), virtual privatenetwork (VPN), cellular telephone network, or any other means oftransferring the video stream from the transmitting station 102 to, inthis example, the receiving station 106.

The receiving station 106, in one example, can be a computer having aninternal configuration of hardware such as that described in FIG. 2.However, other suitable implementations of the receiving station 106 arepossible. For example, the processing of the receiving station 106 canbe distributed among multiple devices.

Other implementations of the video encoding and decoding system 100 arepossible. For example, an implementation can omit the network 104. Inanother implementation, a video stream can be encoded and then storedfor transmission at a later time to the receiving station 106 or anyother device having memory. In one implementation, the receiving station106 receives (e.g., via the network 104, a computer bus, and/or somecommunication pathway) the encoded video stream and stores the videostream for later decoding. In an example implementation, a real-timetransport protocol (RTP) is used for transmission of the encoded videoover the network 104. In another implementation, a transport protocolother than RTP may be used (e.g., a Hypertext Transfer Protocol-based(HTTP-based) video streaming protocol).

When used in a video conferencing system, for example, the transmittingstation 102 and/or the receiving station 106 may include the ability toboth encode and decode a video stream as described below. For example,the receiving station 106 could be a video conference participant whoreceives an encoded video bitstream from a video conference server(e.g., the transmitting station 102) to decode and view and furtherencodes and transmits his or her own video bitstream to the videoconference server for decoding and viewing by other participants.

FIG. 2 is a block diagram of an example of a computing device 200 thatcan implement a transmitting station or a receiving station. Forexample, the computing device 200 can implement one or both of thetransmitting station 102 and the receiving station 106 of FIG. 1. Thecomputing device 200 can be in the form of a computing system includingmultiple computing devices, or in the form of one computing device, forexample, a mobile phone, a tablet computer, a laptop computer, anotebook computer, a desktop computer, and the like.

A processor 202 in the computing device 200 can be a conventionalcentral processing unit. Alternatively, the processor 202 can be anothertype of device, or multiple devices, capable of manipulating orprocessing information now existing or hereafter developed. For example,although the disclosed implementations can be practiced with oneprocessor as shown (e.g., the processor 202), advantages in speed andefficiency can be achieved by using more than one processor.

A memory 204 in computing device 200 can be a read only memory (ROM)device or a random access memory (RAM) device in an implementation.However, other suitable types of storage device can be used as thememory 204. The memory 204 can include code and data 206 that isaccessed by the processor 202 using a bus 212. The memory 204 canfurther include an operating system 208 and application programs 210,the application programs 210 including at least one program that permitsthe processor 202 to perform the techniques described herein. Forexample, the application programs 210 can include applications 1 throughN, which further include a video coding application that performs thetechniques described herein. The computing device 200 can also include asecondary storage 214, which can, for example, be a memory card usedwith a mobile computing device. Because the video communication sessionsmay contain a significant amount of information, they can be stored inwhole or in part in the secondary storage 214 and loaded into the memory204 as needed for processing.

The computing device 200 can also include one or more output devices,such as a display 218. The display 218 may be, in one example, a touchsensitive display that combines a display with a touch sensitive elementthat is operable to sense touch inputs. The display 218 can be coupledto the processor 202 via the bus 212. Other output devices that permit auser to program or otherwise use the computing device 200 can beprovided in addition to or as an alternative to the display 218. Whenthe output device is or includes a display, the display can beimplemented in various ways, including by a liquid crystal display(LCD), a cathode-ray tube (CRT) display, or a light emitting diode (LED)display, such as an organic LED (OLED) display.

The computing device 200 can also include or be in communication with animage-sensing device 220, for example, a camera, or any otherimage-sensing device 220 now existing or hereafter developed that cansense an image such as the image of a user operating the computingdevice 200. The image-sensing device 220 can be positioned such that itis directed toward the user operating the computing device 200. In anexample, the position and optical axis of the image-sensing device 220can be configured such that the field of vision includes an area that isdirectly adjacent to the display 218 and from which the display 218 isvisible.

The computing device 200 can also include or be in communication with asound-sensing device 222, for example, a microphone, or any othersound-sensing device now existing or hereafter developed that can sensesounds near the computing device 200. The sound-sensing device 222 canbe positioned such that it is directed toward the user operating thecomputing device 200 and can be configured to receive sounds, forexample, speech or other utterances, made by the user while the useroperates the computing device 200.

Although FIG. 2 depicts the processor 202 and the memory 204 of thecomputing device 200 as being integrated into one unit, otherconfigurations can be utilized. The operations of the processor 202 canbe distributed across multiple machines (wherein individual machines canhave one or more processors) that can be coupled directly or across alocal area or other network. The memory 204 can be distributed acrossmultiple machines such as a network-based memory or memory in multiplemachines performing the operations of the computing device 200. Althoughdepicted here as one bus, the bus 212 of the computing device 200 can becomposed of multiple buses. Further, the secondary storage 214 can bedirectly coupled to the other components of the computing device 200 orcan be accessed via a network and can comprise an integrated unit suchas a memory card or multiple units such as multiple memory cards. Thecomputing device 200 can thus be implemented in a wide variety ofconfigurations.

FIG. 3 is a diagram of an example of a video stream 300 to be encodedand subsequently decoded. The video stream 300 includes a video sequence302. At the next level, the video sequence 302 includes a number ofadjacent frames 304. While three frames are depicted as the adjacentframes 304, the video sequence 302 can include any number of adjacentframes 304. The adjacent frames 304 can then be further subdivided intoindividual frames, for example, a frame 306. At the next level, theframe 306 can be divided into a series of planes or segments 308. Thesegments 308 can be subsets of frames that permit parallel processing,for example. The segments 308 can also be subsets of frames that canseparate the video data into separate colors. For example, a frame 306of color video data can include a luminance plane and two chrominanceplanes. The segments 308 may be sampled at different resolutions.

Whether or not the frame 306 is divided into segments 308, the frame 306may be further subdivided into blocks 310, which can contain datacorresponding to, for example, 16×16 pixels in the frame 306. The blocks310 can also be arranged to include data from one or more segments 308of pixel data. The blocks 310 can also be of any other suitable sizesuch as 4×4 pixels, 8×8 pixels, 16×8 pixels, 8×16 pixels, 16×16 pixels,or larger. Unless otherwise noted, the terms block and macroblock areused interchangeably herein.

FIG. 4 is a block diagram of an encoder 400 according to implementationsof this disclosure. The encoder 400 can be implemented, as describedabove, in the transmitting station 102, such as by providing a computersoftware program stored in memory, for example, the memory 204. Thecomputer software program can include machine instructions that, whenexecuted by a processor such as the processor 202, cause thetransmitting station 102 to encode video data in the manner described inFIG. 4. The encoder 400 can also be implemented as specialized hardwareincluded in, for example, the transmitting station 102. In oneparticularly desirable implementation, the encoder 400 is a hardwareencoder.

The encoder 400 has the following stages to perform the variousfunctions in a forward path (shown by the solid connection lines) toproduce an encoded or compressed bitstream 420 using the video stream300 as input: an intra/inter prediction stage 402, a transform stage404, a quantization stage 406, and an entropy encoding stage 408. Theencoder 400 may also include a reconstruction path (shown by the dottedconnection lines) to reconstruct a frame for encoding of future blocks.In FIG. 4, the encoder 400 has the following stages to perform thevarious functions in the reconstruction path: a dequantization stage410, an inverse transform stage 412, a reconstruction stage 414, and aloop filtering stage 416. Other structural variations of the encoder 400can be used to encode the video stream 300.

When the video stream 300 is presented for encoding, respective adjacentframes 304, such as the frame 306, can be processed in units of blocks.At the intra/inter prediction stage 402, respective blocks can beencoded using intra-frame prediction (also called intra-prediction) orinter-frame prediction (also called inter-prediction). In any case, aprediction block can be formed. In the case of intra-prediction, aprediction block may be formed from samples in the current frame thathave been previously encoded and reconstructed. In the case ofinter-prediction, a prediction block may be formed from samples in oneor more previously constructed reference frames.

Next, the prediction block can be subtracted from the current block atthe intra/inter prediction stage 402 to produce a residual block (alsocalled a residual or prediction residual). The transform stage 404transforms the residual into transform coefficients in, for example, thefrequency domain using block-based transforms. The quantization stage406 converts the transform coefficients into discrete quantum values,which are referred to as quantized transform coefficients, using aquantizer value or a quantization level. For example, the transformcoefficients may be divided by the quantizer value and truncated.

The quantized transform coefficients are then entropy encoded by theentropy encoding stage 408. The entropy-encoded coefficients, togetherwith other information used to decode the block (which may include, forexample, syntax elements such as used to indicate the type of predictionused, transform type, motion vectors, a quantizer value, or the like),are then output to the compressed bitstream 420. The compressedbitstream 420 can be formatted using various techniques, such asvariable length coding (VLC) or arithmetic coding. The compressedbitstream 420 can also be referred to as an encoded video stream orencoded video bitstream, and the terms will be used interchangeablyherein.

The reconstruction path (shown by the dotted connection lines) can beused to ensure that the encoder 400 and a decoder 500 (described belowwith respect to FIG. 5) use the same reference frames to decode thecompressed bitstream 420. The reconstruction path performs functionsthat are similar to functions that take place during the decodingprocess (described below with respect to FIG. 5), including dequantizingthe quantized transform coefficients at the dequantization stage 410 andinverse transforming the dequantized transform coefficients at theinverse transform stage 412 to produce a derivative residual block (alsocalled a derivative residual). At the reconstruction stage 414, theprediction block that was predicted at the intra/inter prediction stage402 can be added to the derivative residual to create a reconstructedblock. The loop filtering stage 416 can be applied to the reconstructedblock to reduce distortion such as blocking artifacts.

Other variations of the encoder 400 can be used to encode the compressedbitstream 420. In some implementations, a non-transform based encodercan quantize the residual signal directly without the transform stage404 for certain blocks or frames. In some implementations, an encodercan have the quantization stage 406 and the dequantization stage 410combined in a common stage.

FIG. 5 is a block diagram of a decoder 500 according to implementationsof this disclosure. The decoder 500 can be implemented in the receivingstation 106, for example, by providing a computer software programstored in the memory 204. The computer software program can includemachine instructions that, when executed by a processor such as theprocessor 202, cause the receiving station 106 to decode video data inthe manner described in FIG. 5. The decoder 500 can also be implementedin hardware included in, for example, the transmitting station 102 orthe receiving station 106.

The decoder 500, similar to the reconstruction path of the encoder 400discussed above, includes in one example the following stages to performvarious functions to produce an output video stream 516 from thecompressed bitstream 420: an entropy decoding stage 502, adequantization stage 504, an inverse transform stage 506, an intra/interprediction stage 508, a reconstruction stage 510, a loop filtering stage512, and an optional post-filtering stage 514. Other structuralvariations of the decoder 500 can be used to decode the compressedbitstream 420.

When the compressed bitstream 420 is presented for decoding, the dataelements within the compressed bitstream 420 can be decoded by theentropy decoding stage 502 to produce a set of quantized transformcoefficients. The dequantization stage 504 dequantizes the quantizedtransform coefficients (e.g., by multiplying the quantized transformcoefficients by the quantizer value), and the inverse transform stage506 inverse transforms the dequantized transform coefficients to producea derivative residual that can be identical to that created by theinverse transform stage 412 in the encoder 400. Using header informationdecoded from the compressed bitstream 420, the decoder 500 can use theintra/inter prediction stage 508 to create the same prediction block aswas created in the encoder 400 (e.g., at the intra/inter predictionstage 402).

At the reconstruction stage 510, the prediction block can be added tothe derivative residual to create a reconstructed block. The loopfiltering stage 512 can be applied to the reconstructed block to reduceblocking artifacts (e.g., using deblocking filtering, sample adaptiveoffset filtering, or the like, or a combination thereof). Otherfiltering can be applied to the reconstructed block. In this example,the post-filtering stage 514 is applied to the reconstructed block toreduce blocking distortion, and the result is output as the output videostream 516. The output video stream 516 can also be referred to as adecoded video stream, and the terms will be used interchangeably herein.Other variations of the decoder 500 can be used to decode the compressedbitstream 420. In some implementations, the decoder 500 can produce theoutput video stream 516 without the post-filtering stage 514.

Techniques for encoding or decoding video frames are now described withrespect to FIGS. 6 and 7. FIG. 6 is a flowchart diagram of an example ofa technique 600 for encoding a current block of a video frame using sameframe motion estimation. FIG. 7 is a flowchart diagram of an example ofa technique 700 for decoding a current block of a video frame using sameframe motion compensation. One or both of the technique 600 or thetechnique 700 can be implemented, for example, as a software programthat may be executed by computing devices such as the transmittingstation 102 or the receiving station 106. For example, the softwareprogram can include machine-readable instructions that may be stored ina memory such as the memory 204 or the secondary storage 214, and that,when executed by a processor, such as the processor 202, may cause thecomputing device to perform one or both of the technique 600 or thetechnique 700. One or both of the technique 600 or the technique 700 canbe implemented using specialized hardware or firmware, for example, thehardware components 1000 and 1100 described below with respect to FIGS.10 and 11. As explained above, some computing devices may have multiplememories or processors, and the operations described in the technique600 and the technique 700 can be distributed using multiple processors,memories, or both.

For simplicity of explanation, the technique 600 and the technique 700are each depicted and described as a series of steps or operations.However, the steps or operations in accordance with this disclosure canoccur in various orders and/or concurrently. Additionally, other stepsor operations not presented and described herein may be used.Furthermore, not all illustrated steps or operations may be required toimplement a technique in accordance with the disclosed subject matter.

Referring first to FIG. 6, the technique 600 for encoding a currentblock of a video frame using same frame motion estimation is shown. At602, a first set of motion vector candidates is identified by performingmotion estimation based on data stored in a memory (e.g., a local SRAM,an external DRAM, or the like). The first set of motion vectorcandidates includes at least one motion vector that may be used togenerate a prediction block for the current block. The video frame maybe a key frame. Alternatively, the video frame may be an intra-frame, aninter-frame, or another type of video frame.

The data stored in the memory is associated with one or more encodedblocks preceding the current block within the video frame. As such, thedata stored in the memory is stored in the memory subsequent to anencoding of the one or more encoded blocks. For example, a first blockof the video frame may be predicted, transformed, quantized,reconstructed, and filtered. Subsequent to the filtering of the firstblock, data associated with the first block may be stored in the memory,such as for use in encoding a second block of the video frame. In thatthe data associated with the one or more encoded blocks is stored in amemory, the first set of motion vector candidates is identified withouthaving to access a dynamic memory.

The one or more encoded blocks are located within the video frame butoutside of a restricted area of the video frame. The restricted arearefers to a portion of the video frame that is reserved for processing(e.g., such that pixel and/or block data located within the restrictedarea is not yet usable to encode the current block). For example, therestricted area may reflect a portion of the video frame that isreserved for encoder pipeline processing, loop filtering, or the like,or a combination thereof. Examples of the restricted area are describedbelow with respect to FIG. 8. In that there will be more encoded blockswith each block that is processed using the technique 600, there may bemore motion vectors in the first set of motion vector candidates as thetechnique 600 is used to encode blocks of a video frame.

At 604, a second set of motion vector candidates is identified byperforming inter-prediction against at least one encoded block of atleast one previously encoded video frame. The second set of motionvector candidates includes at least one motion vector that may be usedto generate a prediction block for the current block. Operations foridentifying motion vectors by performing inter-prediction are describedabove with respect to the intra/inter prediction stage 402 shown in FIG.4.

At 606, at least one motion vector is selected from the first set ofmotion vector candidates, the second set of motion vector candidates, orboth. Selecting the at least one motion vector can include determiningrate-distortion values resulting from predicting the current block(e.g., using traditional intra-prediction or inter-prediction, or byidentifying common image objects common to other video blocks, such asthe one or more encoded blocks, within the video frame) for the ones ofthe motion vectors of the first set of motion vector candidates and thesecond set of motion vector candidates. A rate-distortion value refersto a function (e.g., a linear function) that balances an amount ofdistortion (e.g., a loss in video quality) with rate (e.g., a number ofbits) for coding a block or other video component. Subsequent todetermining the rate-distortion values, the motion vector candidate orcandidates used to determine a lowest one or more of the rate-distortionvalues is or are selected.

At 608, a prediction residual block is determined for the current block.The prediction residual block is determined by generating a predictionblock based on the selected at least one motion vector. The predictionresidual block represents a difference between the current block to beencoded and the prediction block. Operations for determining aprediction residual block are described above with respect to theintra/inter prediction stage 402 shown in FIG. 4. At 610, the predictionresidual block is transformed to produce transform coefficients.Transforming the prediction residual block can include applying a DCT,ADST, or other transform (or their approximations) to the coefficientsof the prediction residual block to transform the coefficients of theprediction residual block into transform coefficients. Operations fortransforming a prediction residual block are described above withrespect to the transform stage 404 shown in FIG. 4.

At 612, the transform coefficients are quantized to produce quantizationcoefficients. The quantization coefficients represent quantized valuesof pixels reflected in the transformed prediction residual block.Operations for quantizing the transform coefficients are described abovewith respect to the quantization stage 406 shown in FIG. 4. At 614, thequantization coefficients are reconstructed to produce a reconstructedcurrent block. The coefficients of the reconstructed current blockreflects the coefficients of the pixels of the current block before theencoding thereof. Operations for reconstructing the current block aredescribed above with respect to the reconstruction stage 414 shown inFIG. 4 (e.g., based on operations performed at the dequantization stage410 and the inverse transform stage 412 shown in FIG. 4).

At 616, at least a portion of the reconstructed current block isfiltered to produce data indicative of a video object associated withthe reconstructed current block. The filtering can include applying oneor more of a deblocking filter, an SAO filter, or another filter againstone or more pixels of the reconstructed current block. Operations forfiltering the reconstructed current block are described above withrespect to the loop filter stage 416 shown in FIG. 4.

The video object may refer to an object texture or like visual aspectrepresented by the pixel values of the reconstructed current block (and,thus, the current block as received from an input video stream includingthe video frame). For example, when the selected motion vector used todetermine the prediction residual block is selected from the first setof motion vector candidates such that the motion of the current block isestimated using motion estimation based on data stored in a memory, thevideo object may reflect an image pattern also present in one or moreother blocks of the video frame. Alternatively, the video object mayrefer to motion within or otherwise associated with the reconstructedcurrent block (and, thus, the current block). For example, when theselected motion vector used to determine the prediction residual blockis selected from the second set of motion vector candidates such thatthe motion of the current block is predicted using inter-predictionbased on reference frames, the video object may reflect motiondemonstrated using the selected motion vector.

At 618, the data indicative of the video object associated with thereconstructed current block is stored with the in the memory for use inencoding a video block following the current block within the videoframe. Storing the data can include storing one or more of the transformcoefficients of the current block, the motion vector selected forencoding the current block, data indicative of the video objectrepresented by the pixel values of the current block, or the like, or acombination thereof, within the same frame memory from which the datawas received for identifying the first set of motion vector candidates.

In some implementations, the technique 600 includes encoding one or moresyntax elements to a header of the video frame within a bitstream towhich the current block is encoded. The one or more syntax elementsindicate that the first data stored in the same frame memory was used toencode the current block. The one or more syntax elements may, forexample, include one or more bits encoded to a frame header of the videoframe. Alternatively, the one or more syntax elements may be encoded toa slice header, tile header, or other header associated with the videoframe including the current block that was encoded using the first data.The one or more syntax elements reflect that the motion vector selectedfor encoding the current block was selected from the video frame thatincludes the current block. However, in some cases, such as where thevideo frame that includes the current block is a key frame, thetechnique 600 may omit encoding syntax elements to a header of the videoframe.

In some implementations, the technique 600 can include updating acontext model to reflect that a motion vector identified based on sameframe data stored in a memory was used to encode the current block. Forexample, the context model updated based on the use of such anidentified motion vector may be different from context models used fortraditional motion vectors (e.g., those identified from traditionalinter-prediction or intra-prediction). Such a context model reflects thestatistics of using same frame data to encode a current block, forexample, a probability of same frame data being optimal for encoding acurrent block.

Furthermore, the entropy coding of a selected motion vector pointing toa same frame memory may otherwise be different from the entropy codingof a traditional motion vector. For example, in cases where spatialneighbor information is not available for identifying a motion vectorpredictor within the video frame for entropy coding a selected motionvector pointing to a same frame memory, motion estimation may beperformed within the video frame using a spatial neighbor to provide amotion vector predictor. In another example, in that motion vectorspointing to the same frame need to observe boundary constraints distinctfrom those for motion vectors pointing to a different video frame, theremay be range limits observed for the entropy coding of same frame motionvectors.

In some implementations, the first set of motion vector candidatesincludes motion vector candidates identified by performing motionestimation against video blocks of one or more reference frames. Forexample, in bi-directional prediction modes, the encoded blocks usableto perform the motion estimation can be used as one of the referenceframes. One or more other reference frames, for example, past frames orfuture frames, may also be used. In some implementations, the first setof motion vector candidates may include regular motion vectors and/orirregular motion vectors, for example, motion vectors indicatingsub-pixel interpolation, motion warping, or like image changes are used.In some implementations, generating the prediction block can includeusing intra-prediction in addition to or instead of inter-prediction(e.g., for identifying the first and second sets of motion vectors).Operations for generating a prediction block based usingintra-prediction are described above with respect to the intra/interprediction stage 402 shown in FIG. 4.

In some implementations, the technique 600 can be performed to parallelencode current blocks within respective tiles of the video frame.Examples of parallel encoding using tiles is described below withrespect to FIG. 9. In some implementations, the technique 600 can omitthe filtering at 616.

Referring next to FIG. 7, the technique 700 for decoding an encodedblock of an encoded video frame using same frame motion compensation isshown. At 702, one or more syntax elements are decoded from a bitstreamto which the encoded block and encoded video frame are encoded. The oneor more syntax elements indicate to decode the encoded block byperforming motion compensation against one or more reconstructed blocksof the encoded video frame. That is, the one or more syntax elements mayreflect that the encoded block was encoded by performing motionestimation against data representing reconstructed and filtered blockspreceding the encoded block within the encoded video frame.

At 704, motion vectors are decoded from the bitstream and motioncompensation is performed based on data stored in a memory (e.g., alocal SRAM, an external DRAM, or the like). The motion vectors includeat least one motion vector that may be used to generate a predictionblock for the encoded block. The encoded video frame may be a key frame.Alternatively, the encoded video frame may be an intra-frame, aninter-frame, or another type of video frame.

The data stored in the memory is associated with one or more decodedblocks preceding the encoded block within the encoded video frame. Assuch, the data stored in the memory is stored in the memory subsequentto a decoding of the one or more decoded blocks. For example, a firstencoded block of the video frame may be entropy decoded, dequantized,inverse transformed, predicted, reconstructed, and filtered. Subsequentto the filtering of the first encoded block, data associated with thefirst encoded block may be stored in the memory, such as for use indecoding a second encoded block of the encoded video frame. In someimplementations where the data associated with the one or more decodedblocks is stored in a memory, the at least one motion vector can bedecoded without having to access a dynamic memory.

The one or more decoded blocks are located within the encoded videoframe but outside of a restricted area of the encoded video frame. Therestricted area refers to a portion of the encoded video frame that isreserved for processing (e.g., such that pixel and/or block data locatedwithin the restricted area is not yet usable to decode the encodedblock). For example, the restricted area may reflect a portion of theencoded video frame that is reserved for decoder pipeline processing,loop filtering, or the like, or a combination thereof. Examples of therestricted area are described below with respect to FIG. 8. In thatthere will be more decoded blocks with each encoded block that isprocessed using the technique 700, there may be more motion vectorsavailable as the technique 700 is used to decode encoded blocks of anencoded video frame.

At 706, a prediction block is generated for the encoded block using thedecoded at least one motion vector. Operations for generating aprediction block are described above with respect to the intra/interprediction stage 508 shown in FIG. 5. At 708, and separately from theselecting of the at least one motion vector and generating of theprediction block, coefficients of the encoded block are dequantized toproduce dequantization coefficients. The dequantization coefficientsrepresent dequantized values of pixels reflected in the encoded block,such as based on transformation and prediction applied during encoding.Operations for dequantizing the coefficients of the encoded block aredescribed above with respect to the dequantization stage 504 shown inFIG. 5.

At 710, the dequantization coefficients are inverse transformed toreconstruct a prediction residual block. Inverse transforming thedequantization coefficients can include applying a DCT, ADST, or otherinverse transform to the coefficients of the dequantized encoded blockto transform the coefficients of the dequantized encoded block into theprediction residual block. Operations for inverse transforming adequantized encoded block are described above with respect to theinverse transform stage 506 shown in FIG. 5. At 712, the predictionresidual block is combined with the prediction block generated using thedecoded at least one motion vector to produce a reconstructed block. Thecoefficients of the reconstructed block reflect the coefficients of thepixels of the encoded block before the encoding thereof. Operations forreconstructing the encoded block are described above with respect to thereconstruction stage 510 shown in FIG. 5.

At 714, at least a portion of the reconstructed block is filtered toproduce data indicative of a video object associated with thereconstructed block. The filtering can include applying one or more of adeblocking filter, an SAO filter, or another filter against one or morepixels of the reconstructed current block. Operations for filtering thereconstructed block are described above with respect to the loop filterstage 512 shown in FIG. 5.

The video object may refer to an object texture or like visual aspectrepresented by the pixel values of the reconstructed current block (and,thus, the current block as received from an input video stream includingthe video frame). For example, when the decoded motion vector used togenerate the prediction block is identified using motion estimationbased on same frame data stored in a memory, the video object mayreflect an image pattern also present in one or more other blocks of thevideo frame. Alternatively, the video object may refer to motion withinor otherwise associated with the reconstructed current block (and, thus,the current block). For example, when the decoded motion vector used togenerate the prediction block is identified using inter-prediction basedon reference frames, the video object may reflect motion demonstratedusing the selected motion vector.

At 716, the data indicative of the video object associated with thereconstructed block is stored in the memory for use in decoding a videoblock following the encoded block within the encoded video frame.Storing the data can include storing one or more of the reconstructedcoefficients of the reconstructed block, the motion vector selected fordecoding the encoded block, data indicative of the video objectrepresented by the pixel values of the encoded block, or the like, or acombination thereof, within the same frame memory from which the datawas received. This data may later be referred to as same frame data orthe like.

In some implementations, the technique 700 can include updating acontext model to reflect that a motion vector identified based on sameframe data stored in a memory was used to decode the encoded block. Forexample, the context model updated based on the use of such a decodedmotion vector may be different from context models used for traditionalmotion vectors (e.g., those identified from traditional inter-predictionor intra-prediction). Such a context model reflects the statistics ofusing same frame data to decode an encoded block, for example, aprobability of same frame data being optimal for decoding an encodedblock.

Furthermore, the entropy coding of a motion vector pointing to a sameframe memory may otherwise be different from the entropy coding of atraditional motion vector. For example, in cases where spatial neighborinformation is not available for identifying a motion vector predictorwithin the encoded video frame for entropy coding of a motion vectorpointing to a same frame memory, motion estimation may be performedwithin the video frame using a spatial neighbor to provide a motionvector predictor. In another example, in that motion vectors pointing tothe same frame need to observe boundary constraints distinct from thosefor motion vectors pointing to a different encoded video frame, theremay be range limits observed for the entropy coding of same frame motionvectors.

In some implementations, the prediction block may be generated after thedequantizing and inverse transforming. In some implementations, theprediction block may be generated simultaneously or nearly simultaneousto the dequantizing and inverse transforming.

In some implementations, the decoded motion vectors include motionvectors identified by performing motion estimation against video blocksof one or more reference frames. For example, in bi-directionalprediction modes, the decoded blocks usable to perform the motionestimation can be used as one of the reference frames. One or more otherreference frames, for example, past frames or future frames, may also beused. In some implementations, the decoded motion vectors may includeregular motion vectors and/or irregular motion vectors, for example,motion vectors indicating sub-pixel interpolation, motion warping, orlike image changes are used.

In some implementations, the technique 700 can be performed to paralleldecode encoded blocks within respective tiles of the encoded videoframe. Examples of parallel decoding using tiles is described below withrespect to FIG. 9. In some implementations, the technique 700 can omitthe filtering at 714.

FIG. 8 is an illustration of a video frame 800 including a current block802 coded using same frame motion estimation and compensation. The videoframe 800 includes a number of samples available for motion estimationor compensation 804 that have been coded before the current block 802.The video frame 800 also includes a number of uncoded blocks 806 thatwill be coded after the current block 802 is coded. The coding (e.g.,encoding or decoding, as applicable) current block 802 can include usingone or more of the samples available for motion estimation orcompensation 804 to determine a prediction block for the current block802.

For example, data associated with the samples available for motionestimation or compensation 804 may be stored in a memory (e.g., a localSRAM, an external DRAM, or the like) of a hardware component for codingthe current block. The data stored in that memory can be used to performmotion estimation (e.g., during encoding) or motion compensation (e.g.,during decoding) to identify motion vector candidates or otherwisedecode motion vectors that may be used to predict motion of the currentblock. The samples available for motion estimation or compensation 804may include blocks that have already been coded for the video frame 800.The data associated with the samples available for motion estimation orcompensation 804 may be stored within the memory subsequent torespective ones of the blocks of the video frame 800 being coded. Assuch, as more blocks are coded, the size of the portion of the videoframe 800 that includes the samples available for motion estimation andcompensation 804 increases.

The current frame 800 includes one or more restricted areas from whichdata is not used to code the current block 802. The one or morerestricted areas precede the current block 802 within the current frame800 (e.g., according to a scan order for coding the video blocks of thecurrent frame 800, for example, raster scan). For example, a restrictedarea 808 reflects a portion of the current frame 800 that may still beunder process when the current block 802 is ready for coding. Therestricted area 808 may account for operational delay of an encoder ordecoder, for example, delay caused by internal pipeline processing,output buffering, lossless frame compression, system memoryarchitecture, or the like. The restricted area 808 may have a sizeassociated with partition sizes for the current frame 800. For thecurrent block 802 of size N×N, the restricted area 808 may be N pixelsin height and M pixels in width (e.g., where M is a multiple of N). Forexample, where the current block 802 is a 64×64 coding unit, therestricted area 808 may be 64 pixels in height and 192 pixels in width.

In another example, a restricted area 810 reflects a portion of thecurrent frame 800 that will be processed by filtering. The restrictedarea 810 may account for processing by loop filters (e.g., deblockingfilters, SAO filters, or the like). The restricted area 810 includespixels in N rows at the bottom of an entire video block row (e.g., a rowof video blocks that includes the current block 802 within the currentframe 800). The number of rows N is based on the number of pixel linesthat cannot be processed until corresponding lower neighbor video blocksof the corresponding video block row are reconstructed. For example, therestricted area 810 may include three rows of pixels. In some cases, therestricted area 810 may overlap with the restricted area 808. In somecases, the restricted area 810 may be omitted, for example, when loopfiltering, including, but not limited to, deblocking, ConstrainedDirectional Enhancement Filter (CDEF) application, and loop restoration,is not enabled for the current frame 800. In general, the restrictedarea 810 may depend upon what the loop filtering is and how the loopfiltering is used.

FIG. 9 is an illustration of tiles 900, 902 of a video frame 904including current blocks 906, 908 parallel coded using same frame motionestimation and compensation. In some cases, an encoder or decoder usedto code the video frame 904 may not support coding video blocks in aparallel wavefront fashion. This may be, for example, to preventsituations where a motion vector pointing in a direction not yetavailable per the parallel coding order is sought to be used to code avideo block. In such a case, the video frame 904 can be divided intotiles, such as the tiles 900, 902, to enable parallel wavefront codingof video blocks.

Each of the tiles 900, 902 includes samples available for motionestimation or compensation 910, 912, at least some of which may, forexample, be the samples available for motion estimation or compensation804 shown in FIG. 8. Each of the tiles 900, 902 includes uncoded blocks914, 916, at least some of which may, for example, be the uncoded blocks806 shown in FIG. 8. Each of the tiles 900, 902 includes a restrictedarea 918, 920, at least a portion of which may, for example, be one orboth of the restricted area 808 or the restricted area 810 shown in FIG.8. The coding of video blocks using independent tiles 900, 902 may allowfor motion vectors pointing in various directions to be used for motionestimation or compensation, and, therefore, to determine a predictionresidual block for the current blocks 906, 908.

FIG. 10 is a block diagram of a hardware component 1000 configured forencoding a current block of a video frame using same frame motionestimation. The hardware component 1000 may, for example, be animplementation of the encoder 400 shown in FIG. 4. For example, thehardware component 1000 may be a hardware component configured toperform the technique 600 shown in FIG. 6. The hardware component 1000may be a hardware component of a transmitting station, for example, thetransmitting station 102 shown in FIG. 1.

The hardware component 1000 includes a motion estimation memory 1002that receives one or more input reference frames 1004. In someimplementations, the motion estimation memory 1002 may be a local SRAM.In such an implementation, the input reference frames 1004 are receivedby the hardware component 1000 for motion estimation within a local SRAMwithout the hardware component 1000 having to access a DRAM.Alternatively, the motion estimation memory 1002 may be a DRAM externalto the hardware component 1000 or another form of memory. The hardwarecomponent 1000 performs motion estimation 1006 against a current videoframe to encode as one or more input video frames 1008 received by thehardware component 1000. The motion estimation 1006 processes thecurrent video frame based on data output from the motion estimationmemory 1002 and data output from a same frame memory 1010. The sameframe memory 1010 includes data associated with video blocks that havealready been encoded (e.g., reconstructed blocks) within the currentvideo frame to encode. The same frame memory 1010 may, for example, be alocal SRAM, a DRAM external to the hardware component 1000, or anotherform of memory. In at least some cases, the motion estimation memory1002 and the same frame memory 1010 may be the same memory unit.

The hardware component 1000 separately performs intra prediction 1012against the current video frame received as one of the input videoframes 1008. Motion data (e.g., prediction residuals) resulting from themotion estimation 1006 and from the intra prediction 1012 are fed into amode selection 1014 that selects the data resulting from the motionestimation 1006 or the data resulting from the intra prediction 1012 asthe motion data to use to encode a next video block of the current videoframe. For example, the mode selection 1014 can perform arate-distortion analysis against the motion data resulting from themotion estimation 1006 and the motion data resulting from the intraprediction 1012. The prediction residual data selected by the modeselection 1014 is then output for transformation and quantization 1016.After the transformation and quantization 1016, the current block isreconstructed at reconstruction 1018 to produce a reconstructed currentblock.

The reconstructed current block may then be filtered, for example, usingloop filtering 1020. The output of the loop filtering 1020 is used toindicate output reference frames 1022 that may later be used to predictother ones of the input video frames 1008 to be processed. The output ofthe loop filtering 1020 is also fed back into the same frame memory 1010for later use in processing by the motion estimation 1006. As such, dataassociated with a current block of one of the input video frames 1008being encoded using the hardware component 1000 can be used to encode alater block within that one of the input video frames 1008, such as bythat data being used from the same frame memory 1010 to perform a motionestimation 1006 for that later block.

The data associated with the current block may also, subsequent to thereconstruction 1018, be processed within bitstream compression 1024 andoutput to a compressed bitstream 1026. The bitstream compression 1024may, for example, include entropy encoding and/or other operations forencoding the data to the compressed bitstream 1026. The compressedbitstream 1026 is then output to a server for storage, a receivingstation (e.g., the receiving station 106 shown in FIG. 1) for decoding,or the like.

Implementations of the hardware component 1000 may differ from thosedescribed above. In some implementations, an additional memory may beused by the hardware component 1000 to store data associated with videoblocks encoded using the hardware component 1000. Those video blocksmay, for example, be the last video blocks against which a predictorsearch can be performed within the video frame (e.g., based onrestricted areas within the video frame). Using this additional memorywould thus allow for an extra video frame of motion search to be addedwithout a DRAM bandwidth increase.

In some implementations, the hardware component 1000 may omit the loopfiltering 1020. In some implementations, the data output by thetransformation and quantization 1016 may be entropy encoded and outputto the compressed bitstream 1026 without first being reconstructed. Insome implementations, the hardware component 1000 may includefunctionality for decoding an encoded block, for example, by performingall or a portion of the technique 700. For example, the hardwarecomponent 1000 may include the functionality described below withrespect to the hardware component 1100 shown in FIG. 11. In anotherexample, the hardware component 1000 and the hardware component 1100 maybe a single hardware component.

FIG. 11 is a block diagram of a hardware component 1100 configured fordecoding an encoded block of an encoded video frame using same framemotion compensation. The hardware component 1100 may, for example, be animplementation of the decoder 500 shown in FIG. 5. For example, thehardware component 1100 may be a hardware component configured toperform the technique 700 shown in FIG. 7. The hardware component 1100may be a hardware component of a receiving station, for example, thereceiving station 106 shown in FIG. 1.

The hardware component 1100 receives a compressed bitstream 1102, whichmay, for example, be the compressed bitstream 1026 shown in FIG. 10. Thecompressed bitstream 1102 includes data associated with one or moreencoded frames of an encoded video stream. The compressed bitstream 1102is first processed using an entropy decoder 1104. Motion compensation1106 is then performed against the entropy decoded data. The motioncompensation 1106 is performed using data from motion compensationmemory 1108 and using data output from a same frame memory 1110. Themotion compensation memory 1108 receives one or more input referenceframes 1112. In some implementations, the input reference frames 1112may be received by the hardware component 1100 for motion compensationwithin a local SRAM without the hardware component 1100 having to accessa DRAM. The same frame memory 1110 includes data associated with encodedblocks that have already been decoded within the encoded video frame todecode. One or both of the motion compensation memory 1108 or the sameframe memory 1110 may be a local SRAM, a DRAM external to the hardwarecomponent 1100, or another form of memory. In at least some cases, themotion compensation memory 1108 and the same frame memory 1110 may bethe same memory unit.

The hardware component 1100 separately outputs the entropy decoded dataassociated with the encoded block for dequantization and inversetransformation 1114. After the dequantization and inverse transformation1114, the encoded block is reconstructed at reconstruction 1118 toproduce a reconstructed block. The hardware component 1100 furtherseparately performs intra prediction 1116 against the encoded videoframe received within the compressed bitstream 1102 (e.g., based on oneor more already decoded blocks within the encoded video frame). Motiondata (e.g., prediction blocks) resulting from the motion compensation1106 and from the intra prediction 1116 are received and used by thereconstruction 1118, such as to reconstruct the encoded block.

The reconstructed block is then filtered, for example, using loopfiltering 1120. The output of the loop filtering 1120 is used toindicate output reference frames 1122 that may later be used to predictother encoded blocks and encoded video frames from the compressedbitstream 1102. The output of the loop filtering 1120 is also fed backinto the same frame memory 1110 for later use in processing by themotion compensation 1106. As such, data associated with an encoded blockof an encoded video frame being decoded from the compressed bitstream1102 using the hardware component 1100 can be used to decode a laterencoded block within that encoded video frame, such as by that databeing used from the same frame memory 1110 to perform a motioncompensation 1106 for that later block. The data associated with theencoded block may also, subsequent to the loop filtering 1120, be outputto one or more output video frames 1124, such as for display as part ofan output video stream.

Implementations of the hardware component 1100 may differ from thosedescribed above. In some implementations, an additional memory may beused by the hardware component 1100 to store data associated withencoded blocks decoded using the hardware component 1100. Those encodedblocks may, for example, be the last encoded blocks against which apredictor search can be performed within the encoded frame (e.g., basedon restricted areas within the encoded frame). Using this additionalmemory would thus allow for an extra video frame of motion search to beadded, for example, without a DRAM bandwidth increase.

In some implementations, the hardware component 1100 may includefunctionality for encoding a video block, for example, by performing allor a portion of the technique 600. For example, the hardware component1100 may include the functionality described above with respect to thehardware component 1000 shown in FIG. 10. In another example, thehardware component 1000 and the hardware component 1100 may be a singlehardware component.

The aspects of encoding and decoding described above illustrate someexamples of encoding and decoding techniques and hardware componentsconfigured to perform all or a portion of those examples of encodingand/or decoding techniques. However, it is to be understood thatencoding and decoding, as those terms are used in the claims, could meancompression, decompression, transformation, or any other processing orchange of data.

The word “example” is used herein to mean serving as an example,instance, or illustration. Any aspect or design described herein as“example” is not necessarily to be construed as being preferred oradvantageous over other aspects or designs. Rather, use of the word“example” is intended to present concepts in a concrete fashion. As usedin this application, the term “or” is intended to mean an inclusive “or”rather than an exclusive “or.” That is, unless specified otherwise orclearly indicated otherwise by the context, the statement “X includes Aor B” is intended to mean a natural inclusive permutation thereof. Thatis, if X includes A; X includes B; or X includes both A and B, then “Xincludes A or B” is satisfied under any of the foregoing instances. Inaddition, the articles “a” and “an” as used in this application and theappended claims should generally be construed to mean “one or more,”unless specified otherwise or clearly indicated by the context to bedirected to a singular form. Moreover, use of the term “animplementation” or the term “one implementation” throughout thisdisclosure is not intended to mean the same embodiment or implementationunless described as such.

Implementations of the transmitting station 102 and/or the receivingstation 106 (and the algorithms, methods, instructions, etc., storedthereon and/or executed thereby, including by the encoder 400 and thedecoder 500) can be realized in hardware, software, or any combinationthereof. The hardware (e.g., the hardware component 1000 and/or thehardware component 1100) can include, for example, computers,intellectual property (IP) cores, application-specific integratedcircuits (ASICs), programmable logic arrays, optical processors,programmable logic controllers, microcode, microcontrollers, servers,microprocessors, digital signal processors, or any other suitablecircuit. In the claims, the term “processor” should be understood asencompassing any of the foregoing hardware, either singly or incombination. The terms “signal” and “data” are used interchangeably.Further, portions of the transmitting station 102 and the receivingstation 106 do not necessarily have to be implemented in the samemanner.

Further, in one aspect, for example, the transmitting station 102 or thereceiving station 106 can be implemented using a general purposecomputer or general purpose processor with a computer program that, whenexecuted, carries out any of the respective methods, algorithms, and/orinstructions described herein. In addition, or alternatively, forexample, a special purpose computer/processor can be utilized which cancontain other hardware for carrying out any of the methods, algorithms,or instructions described herein.

The transmitting station 102 and the receiving station 106 can, forexample, be implemented on computers in a video conferencing system.Alternatively, the transmitting station 102 can be implemented on aserver, and the receiving station 106 can be implemented on a deviceseparate from the server, such as a handheld communications device. Inthis instance, the transmitting station 102, using an encoder 400, canencode content into an encoded video signal and transmit the encodedvideo signal to the communications device. In turn, the communicationsdevice can then decode the encoded video signal using a decoder 500.Alternatively, the communications device can decode content storedlocally on the communications device, for example, content that was nottransmitted by the transmitting station 102. Other suitable transmittingand receiving implementation schemes are available. For example, thereceiving station 106 can be a generally stationary personal computerrather than a portable communications device, and/or a device includingan encoder 400 may also include a decoder 500.

Further, all or a portion of implementations of the present disclosurecan take the form of a computer program product accessible from, forexample, a computer-usable or computer-readable medium. Acomputer-usable or computer-readable medium can be any device that can,for example, tangibly contain, store, communicate, or transport theprogram for use by or in connection with any processor. The medium canbe, for example, an electronic, magnetic, optical, electromagnetic, orsemiconductor device. Other suitable mediums are also available.

The above-described embodiments, implementations, and aspects have beendescribed in order to facilitate easy understanding of this disclosureand do not limit this disclosure. On the contrary, this disclosure isintended to cover various modifications and equivalent arrangementsincluded within the scope of the appended claims, which scope is to beaccorded the broadest interpretation as is permitted under the law so asto encompass all such modifications and equivalent arrangements.

What is claimed is:
 1. A method for encoding a current block of a videoframe, the method comprising: identifying a first set of motion vectorcandidates by performing motion estimation based on first data stored ina memory, the first data associated with one or more encoded blockspreceding the current block within the video frame, the first datastored in the memory subsequent to an encoding of the one or moreencoded blocks; identifying a second set of motion vector candidates byperforming inter-prediction against at least one encoded block of atleast one previously encoded video frame; selecting at least one motionvector from at least one of the first set of motion vector candidates orthe second set of motion vector candidates; determining a predictionresidual block for the current block using a prediction block generatedbased on the selected at least one motion vector; transforming theprediction residual block to produce transform coefficients; quantizingthe transform coefficients to produce quantization coefficients;reconstructing the quantization coefficients to produce a reconstructedcurrent block; and storing second data in the memory for use in encodinga video block following the current block within the video frame, thesecond data indicative of a video object associated with thereconstructed current block.
 2. The method of claim 1, wherein the oneor more encoded blocks are outside of a restricted area of the videoframe, the restricted area reflecting a portion of the video framereserved for encoder pipeline processing.
 3. The method of claim 1,wherein the first set of motion vector candidates is identified withoutaccessing a dynamic memory.
 4. The method of claim 1, wherein theselected at least one motion vector is selected from the first set ofmotion vector candidates, the method further comprising: encoding one ormore syntax elements to a header of the video frame within a bitstreamto which the current block is encoded, the one or more syntax elementsindicating that the first data was used to encode the current block. 5.The method of claim 1, wherein the first set of motion vector candidatesincludes one or more motion vector candidates identified by performingmotion estimation against video blocks of one or more reference frames.6. The method of claim 1, wherein the memory is one of a local staticrandom access memory or an external dynamic random access memory.
 7. Themethod of claim 1, further comprising: filtering at least a portion ofthe reconstructed current block to produce the second data.
 8. Anapparatus for encoding a current block of a video frame, the apparatuscomprising: a processor configured to execute instructions stored in anon-transitory storage medium to: identify a first set of motion vectorcandidates by performing motion estimation based on first data stored ina memory, the first data associated with one or more encoded blockspreceding the current block within the video frame, the first datastored in the memory subsequent to an encoding of the one or moreencoded blocks; identify a second set of motion vector candidates byperforming inter-prediction against at least one encoded block of atleast one previously encoded video frame; select at least one motionvector from at least one of the first set of motion vector candidates orthe second set of motion vector candidates; determine a predictionresidual block for the current block using a prediction block generatedbased on the selected at least one motion vector; transform theprediction residual block to produce transform coefficients; quantizethe transform coefficients to produce quantization coefficients;reconstruct the quantization coefficients to produce a reconstructedcurrent block; and store second data in the memory for use in encoding avideo block following the current block within the video frame, thesecond data indicative of a video object associated with thereconstructed current block.
 9. The apparatus of claim 8, wherein theone or more encoded blocks are outside of a restricted area of the videoframe, the restricted area reflecting a portion of the video framereserved for encoder pipeline processing.
 10. The apparatus of claim 8,wherein the first set of motion vector candidates is identified withoutaccessing a dynamic memory.
 11. The apparatus of claim 8, wherein theselected at least one motion vector is selected from the first set ofmotion vector candidates, wherein the instructions include instructionsto: encode one or more syntax elements to a header of the video framewithin a bitstream to which the current block is encoded, the one ormore syntax elements indicating that the first data was used to encodethe current block.
 12. The apparatus of claim 8, wherein the first setof motion vector candidates includes one or more motion vectorcandidates identified by performing motion estimation against videoblocks of one or more reference frames.
 13. The apparatus of claim 8,wherein the memory is one of a local static random access memory or anexternal dynamic random access memory.
 14. The apparatus of claim 8,wherein the instructions include instructions to: filter at least aportion of the reconstructed current block to produce the second data.15. A method for decoding an encoded block of an encoded video framefrom a bitstream, the method comprising: decoding one or more syntaxelements from the bitstream, the one or more syntax elements indicatingto decode the encoded block by performing motion compensation againstone or more reconstructed blocks of the encoded video frame; decoding atleast one motion vector from the bitstream and performing motioncompensation based on first data stored in a memory, the first dataassociated with the one or more reconstructed blocks, the first datastored in the memory subsequent to a reconstruction of the one or morereconstructed blocks; generating a prediction block using the decoded atleast one motion vector; dequantizing coefficients of the encoded blockto produce dequantization coefficients; inverse transforming thedequantization coefficients to reconstruct a prediction residual block;combining the prediction residual block and the prediction block toproduce a reconstructed block; and storing second data in the memory foruse in decoding a video block following the encoded block within theencoded video frame, the second data indicative of a video objectassociated with the reconstructed block.
 16. The method of claim 15,wherein the one or more decoded blocks are outside of a restricted areaof the encoded video frame, the restricted area reflecting a portion ofthe encoded video frame reserved for decoder pipeline processing. 17.The method of claim 15, wherein the decoded at least one motion vectoris identified without accessing a dynamic memory.
 18. The method ofclaim 15, wherein the decoded at least one motion vector includes one ormore motion vectors identified using one or more reference frames. 19.The method of claim 15, wherein the encoded video frame is a key frame,wherein the memory is one of a local static random access memory or anexternal dynamic random access memory.
 20. The method of claim 15,further comprising: filtering at least a portion of the reconstructedblock to produce the second data.